Totally cook from scratch. Firstly I know whats going into the food. I have a well stocked and well used larder. I make my own bread, as I can't stand the majority of bulk baked bread.
The cost factor is a personal decision. I would rather spend cash on ingredients, than say buy Lotto tickets. Then there is the enjoyment of making my own food, adding personal choices is part of the fun. I make time each day to cook, it is relaxing and creative.